export {}

// let str1 = 'hello TS' // string

// const str2 = 'hello TS'

// let str1: string  = 'hello TS' // string

// const str2 : 'hello TS' = 'hello TS'

// const a: 10 = 10
 
type Gender = 'girl' | 'boy' | 'abc'

let gender:Gender = 'girl' // 'boy'

// 这里会对gender做判断，赋值......

if(gender === "") {
    
} else if(gender === "boy") {

}
